设计模式-行为篇（策略模式）

策略模式

一个类的行为或其算法可以在运行时更改。

一个接口calculate进行规范
然后add,subtraction 都继承该接口，实现自己特定的行为。

/**
 * Created by malei on 2016/12/6.
 */
public class Computer {

    private final Calculate calculate;

    public Computer(Calculate calculate){
        this.calculate = calculate;
    }

    public int exe(int a, int b){
        return calculate.operate(a,b);
    }

    public static void main(String[] args){
        Computer add = new Computer(new AddOperate());
        Computer sub = new Computer(new SubtraOperate());
        Log.show(add.exe(1,1));
        Log.show(sub.exe(1,1));
    }
}

/**
 * Created by malei on 2016/12/6.
 * 相加操作
 */
public class AddOperate implements Calculate{
    @Override
    public int operate(int a, int b) {
        return a+b;
    }
}

/**
 * Created by malei on 2016/12/6.
 */
public class SubtraOperate implements Calculate{
    @Override
    public int operate(int a, int b) {
        return a-b;
    }
}

/**
 * Created by malei on 2016/12/6.
 * 数学计算接口规范
 */
public interface Calculate {
    int operate(int a,int b);
}